Brake control for turret cranes



Sept. 1, 1931. V T. N. GARSON 1,821,333

BRAKE CONTROL FOR TURBET CRANES Filed June 21, 1928 uzz J44.

ATTORNEY Patented Sept. 1, 1931 HEB ATES PATENT OFFICE BRAKE CONTROL FOB, TURRET G'B-ANES Application filed June 21,

The present invention relates to a brake for a turret crane of that type adapted to be mounted upon a tractor, and in which the primary crane elements comprise a standard, a

hollow mast or turret which revolves about the standard, a boom mounted upon the turret and means for raising and lowering the boom. lhe standard and turret are so formed that the two may be operated as coacting braking members in order to control the swinging movements of the turret.

The invention will be described with reference to the accompanying drawings, in which- Figure 1 is a view in elevation of an embodiment of the invention;

Figure 2 is an enlarged sectional detail of the standard, turret and their associated members;

Figure 3 is a horizontal section on the line 33, Figure 2, and

Figure 4 is an enlarged fragmentary plan view of certain of the standard and turret members.

In the drawings I have illustrated, diagrammatically, a tractor A having vertical frame members 1 and horizontal frame members 2, a front axle 3 and a rear axle 4. Frame members 2 support a horizontal table 5 upon which is suitably secured a hollow standard 6. Standard 6 is formed with an annular vertical wall section 6*, the standard then tapering upward to correspond with the similarly formed turret 7. lhe turret is mounted to rotate about the standard. Near its base the turret is formed with a bracket arm 7-, upon which is pivotally mounted a boom 8. At the end of the boom is a sheave 40 9. A hoist rope 10 is led over sheave 9 through the pulley 11 of block 12 over a guide sheave 13 and thence to a stay 14 at the top of the turret. The hoist rope 10 may be led over a pulley 14, and thence through the-hollow mast to any suitable means for winding in, such as the drum.

A cable 15 may be connected to the boom near its end and thence to a suitable automatic take-up drum 16 which may be of the construction set forth in my co-pending ap 1928. Serial No. 287,067.

plication filed February 20, 1926, Serial No. 89,530.

Connected to the usual power shaft 17 of the tractor is a sprocket wheel 18 connected by drive chain 19 to the sprocket wheel 20 on shaft 21, which may be power connected to the wind-in drum and also to a shaft 22 which may be directly or indirectly connected with the turret for revolving it. In the present embodiment the turret is provided with horizontally projecting arms 23 upon which is bolted a ring 24. Secured to ring 24 and depending therefrom is a channel-ring 25 carrying a gear ring26. Gear ring 26 is in mesh with a pinion 27 carried by shaft 22.

Channel-ring 25 serves as the contacting surface of a brake which comprises said ring and certain members carried by the standard and now to be described.

Bolted upon the standard 6 is a plate 28 7 formed with aslot 29 through which passes a pivot stud 30, the stud having a reduced lower end which is threaded and which receives a nut 31 by means of which the stud may be clamped upon said plate 28. Opposite slot 29 is a second slot 29 which receives a stud 33 of the same formation as stud 30 and which likewise is clamped upon plate 28. Stud 30 pivotally supports brake segment 34 which is faced with a brake lining 35. Stud 33 pivotally supports one end of brake segment 36 faced with a brake lining 37 Each brake segment at its end opposite the pivotal end carries an angular bracket 38 and between the brackets is a cam 40. 8 Cam 40 is disposed at the upper end of a shaft 41, which shaft is pivotally supported by a plate 42 bolted to the standard 6. At the lower end of shaft 41 is disposed an operating lever 42".

In the operation of the device the turret is free for rotation about the standard either 7 under the action of the power gear ring and pinion 26, 27 or otherwise. When it is desired to slow up or stop the movement of the turret, lever 42 may be thrown toward the dotted line position, Fig. 3, which will cause movement of the bracket members 38 in opposite directions and the expanding of the ,7 brake segments so that facings 35, 37 will be carried into adjustable contact with the channel-ring 25.

It will be noted that by loosening nuts 31, studs 30 may be moved in a direction away from each other so as to bring the brake lining toward the ring to compensate for wear. The nuts may then be tightened to hold the studs in position. The force thrown upon the studs in the braking operation tends to move them toward each other. In order to offset such force I have provided a wedge-block 43 disposed intermediate the studs 30, 33 and secured to plate 80 through the intermediary of a clamping bolt 4A which passes through a slot formed in the block.

Having described my invention what I claim and desire to secure by Letters Patent is as follows In devices of the character described, in

.cluding' a standard and a turret rotatable about the standard, of brake mechanism comprising arms projected laterally from the turret, a channel-ring depending from said arms, a plate carried by the standard below said arms, opposed studs carried by one of said plates, brake segments each having a connection with one of said pivot studs, a second plate carried by the standard below said arms, a cam supported by said plate and means for actuating said cam into operative engagement with the brake segments.

In testimony whereof, I have signed my name to this specification.

THORVALD N. GARSON. 

